Some of apparatus having the function of reading an original such as copying machines, facsimile apparatus, etc. have a mechanism for automatically conveying the original and a mechanism for automatically aligning the leading end edge of the original being conveyed. Some of the aligning devices of these prior art mechanisms move movable guide plates provided at one or both sides of an obliquely conveyed original to align such original before it reaches a reading portion, and force the sides of the oblique original by the guide plates, thereby correcting the conveyance direction of the original. Also, as a high-degree aligning device, it would occur to mind to detect the condition of an original being conveyed and move conveyor rollers to a desired position in the direction of their rotational axis as required or rotate the rollers until the leading end edge of the original assumes a desired state.
The above-described mechanisms are complicated in construction and, where the guide plates and the rollers are large in size, the original to be corrected must have a predetermined thickness or self-supporting strength, and it is difficult to cause these mechanisms to effectively act for very thin originals such as air mail paper. Also, mechanisms which do not have the above-described aligning devices are cumbersome to use because the operator of the copying machine or the like must convey an original while confirming the position of the original relative to the guide plate or guide line.
It is therefore the object of the present invention to provide an original aligning device which can align thin originals by a simple construction.